Here's some things that I've tried, some of them maybe didn't work for me but it's worth giving them a try I guess.
- Remove and then re-add the server to the list.
- Disable and re-enabe the network adapter
- Reinstall SA:MP
- Restart your PC (Most likely not going to do anything)
- Restart your router, turn it off and keep it like that for 5-10 minutes then turn it back on, someone people said that that fixed their problem.
- Disable the Windows Defender Firewall
- Delete samp.cfg and userdata.dat
- Connect with the numerical IP
- Delete the SAMP folder in GTASA User Files completely.
- Reinstall GTA:SA completely
- Try the ipconfing /flushdns method, and ipconfig /release > ipconfig /renew method.
(Hold down Win+R then type in cmd, click enter, when it opems type in ipconfig /flushdns or the other method - you might lose internet for a few seconds.)
- Run the RCRP diagnostics tool and paste the results, hopefully someone who understands it could be able to help you.
- Reset your PC/reinstall Windows, unless you've got something you don't want to lose or just are too lazy to do it.
- Last resort: Post a support ticket on the UCP and request to use a VPN.
